<template>
    <div class="app-container">
      <!--查询表单-->
        <el-form :inline="true" class="demo-form-inline">
        <!-- 所属分类：级联下拉列表 -->
        <!-- 一级分类 -->
        <el-form-item label="课程类别">
            <el-select
            v-model="searchObj.subjectParentId"
            placeholder="请选择"
            @change="subjectLevelOneChanged">
            <el-option
                v-for="subject in subjectOneList"
                :key="subject.id"
                :label="subject.title"
                :value="subject.id"/>
            </el-select>
            <!-- 二级分类 -->
            <el-select v-model="searchObj.subjectId" placeholder="请选择">
            <el-option
                v-for="subject in subjectTowList"
                :key="subject.id"
                :label="subject.title"
                :value="subject.id"/>
            </el-select>
        </el-form-item>
        <!-- 标题 -->
        <el-form-item>
            <el-input v-model="searchObj.title" placeholder="课程标题"/>
        </el-form-item>
        <!-- 讲师 -->
        <el-form-item>
            <el-select
            v-model="searchObj.teacherId"
            placeholder="请选择讲师">
            <el-option
                v-for="teacher in teacherList"
                :key="teacher.id"
                :label="teacher.name"
                :value="teacher.id"/>
            </el-select>
        </el-form-item>
        <el-button type="primary" icon="el-icon-search" @click="getCourse()">查询</el-button>
        <el-button type="default" @click="resetData()">清空</el-button>
        </el-form>

        <!-- 表格 -->
        <el-table
        v-loading="listLoading"
        :data="list"
        element-loading-text="数据加载中"
        border
        fit
        highlight-current-row
        row-class-name="myClassList">
        <el-table-column
            label="序号"
            width="70"
            align="center">
            <template slot-scope="scope">
            {{ (page - 1) * limit + scope.$index + 1 }}
            </template>
        </el-table-column>
        <el-table-column label="课程信息" width="450" align="center">
            <template slot-scope="scope">
            <div class="info">
                <div class="pic">
                <img :src="scope.row.cover" alt="scope.row.title" width="150px">
                </div>
                <div class="title">
                <a @click="updateCousePublish(scope.row.id)">{{ scope.row.title }}</a>
                <p>{{ scope.row.lessonNum }}课时</p>
                </div>
            </div>
            </template>
        </el-table-column>
        <el-table-column label="创建时间" align="center">
            <template slot-scope="scope">
            {{ scope.row.gmtCreate.substr(0, 10) }}
            </template>
        </el-table-column>
        <el-table-column label="发布时间" align="center">
            <template slot-scope="scope">
            {{ scope.row.gmtModified.substr(0, 10) }}
            </template>
        </el-table-column>
        <el-table-column label="价格" width="85" align="center" >
            <template slot-scope="scope">
            {{ Number(scope.row.price) === 0 ? '免费' :
            '¥' + scope.row.price.toFixed(2) }}
            </template>
        </el-table-column>
        <el-table-column label="课程状态" width="65" align="center" >
            <template slot-scope="scope">
                {{ scope.row.status === 'Normal' ? '已发布' :
            '未发布' }}
            </template>
        </el-table-column>
        <el-table-column label="浏览数量" width="50" align="center" >
            <template slot-scope="scope">
                {{ scope.row.viewCount }}
            </template>
        </el-table-column>
        <el-table-column prop="buyCount" label="付费学员" width="100" align="center" >
            <template slot-scope="scope">
            {{ scope.row.buyCount }}人
            </template>
        </el-table-column>
        <el-table-column label="操作" width="150" align="center">
            <template slot-scope="scope">
            <!-- <router-link :to="'/edu/course/info/'+scope.row.id"> -->
                <el-button type="text" size="mini" icon="el-icon-edit" @click="updateCourseInfo(scope.row.id)">编辑课程信息</el-button>
            <!-- </router-link> -->
            <!-- <router-link :to="'/edu/course/chapter/'+scope.row.id"> -->
                <el-button type="text" size="mini" icon="el-icon-edit" @click="updateCourseChapterVideo(scope.row.id)">编辑课程大纲</el-button>
            <!-- </router-link> -->
            <el-button type="text" size="mini" icon="el-icon-delete" @click="removeCourse(scope.row.id)">删除</el-button>
            </template>
        </el-table-column>
        </el-table>
        <!-- 分页 -->
        <el-pagination
        :current-page="page"
        :page-size="limit"
        :total="total"
        style="padding: 30px 0; text-align: center;"
        layout="total, prev, pager, next, jumper"
        @current-change="getCourse"
        />

    </div>
</template>

<script>
import course from '@/api/edu/course'
import teacher from '@/api/edu/teacher'
import subject from '@/api/edu/subject'
export default {
    data(){
        return{
            listLoading: true, // 是否显示loading信息
            list: null, // 数据列表
            total: 0, // 总记录数
            page: 1, // 页码
            limit: 10, // 每页记录数
            searchObj: {
                // 这个是我们搜索条件里面的一级分类
                subjectParentId: '',
                // 这个是我们搜索条件里面的二级分类
                subjectId: '',
                title: '',
                teacherId: ''
            }, // 查询条件
            teacherList: [], // 讲师列表
            subjectOneList: [], // 一级分类列表
            subjectTowList: [] // 二级分类列表,

        }
    },
    created(){
        // 当页面加载时获取数据
        this.getCourse()
        // 初始化分类列表
        this.initSubjectList()
        // 获取讲师列表
        this.initTeacherList()
    },
    methods:{
        // 编辑章节信息
        updateCourseChapterVideo(id){
            this.$router.push({path:'/course/chapter/' + id})
        },

        // 编辑课程基本信息(理由跳转)
        updateCourseInfo(id){
            this.$router.push({path:'/course/info/' + id})
        },
        // 编辑章节信息
        updateCousePublish(id){
            this.$router.push({path:'/course/publish/' + id})
        },

        // 删除课程
        removeCourse(id){
                // debugger
            this.$confirm('此操作将永久删除该课程，以及该课程下的章节和视频，是否继续?', '提示', {
                confirmButtonText: '确定',
                cancelButtonText: '取消',
                type: 'warning'
            }).then(() => {
                return course.removeCourse(id)
            }).then(() => {
                this.getCourse(this.page)
                this.$message({
                    type: 'success',
                    message: '删除成功!'
                })
            }).catch((response) => { // 失败
                if (response === 'cancel') {
                    this.$message({
                        type: 'info',
                        message: '已取消删除'
                    })
                }
            })
        },
        

        // 清空按钮
        resetData(){
            this.searchObj = {}
            // 因为这个是我们自动赋值上去的
            this.subjectTowList = [] // 二级分类列表
            // 重新查询一下
            this.getCourse()
        },

        // 初始的时候 page = 1
        getCourse(page = 1){
            this.page = page
            // 那个加载框
            this.listLoading = true
            course.getListCourse(this.page, this.limit, this.searchObj).then(resp => {
                this.list = resp.data.rows
                this.total = resp.data.total
                // 关闭加载框
                this.listLoading = false
            })
        },
        // 初始化所有的老师 让我们进行选择
        initTeacherList(){
            teacher.getList().then(resp => {
                this.teacherList = resp.data.items
            })
        },

        // 初始化分类列表
        initSubjectList(){
            subject.getSubjectList().then(resp => {
                this.subjectOneList = resp.data.oneSubject
            })
        },
        // 这个就是你的一级分类进行了改变那么我们就要查出起对应的二级分类
        // 但是都是存在我们的 subjectOneList里面了
        // 这个value对我们一级分类的id 进行了包装的
        subjectLevelOneChanged(value){
            for(var i=0; i < this.subjectOneList.length;i++){
                // 就是我们所点击的那个一级分类
                if(this.subjectOneList[i].id === value){
                    this.subjectTowList = this.subjectOneList[i].children
                    this.searchObj.subjectId = ''
                }
            }
        }

    }
}
</script>   
<style scoped>
    .myClassList .info {
        width: 450px;
        overflow: hidden;
    }
    .myClassList .info .pic {
        width: 150px;
        height: 90px;
        overflow: hidden;
        float: left;
    }
    .myClassList .info .pic a {
        display: block;
        width: 100%;
        height: 100%;
        margin: 0;
        padding: 0;
    }
    .myClassList .info .pic img {
        display: block;
        width: 100%;
    }
    .myClassList td .info .title {
        width: 280px;
        float: right;
        height: 90px;
    }
    .myClassList td .info .title a {
        display: block;
        height: 48px;
        line-height: 24px;
        overflow: hidden;
        color: #00baf2;
        margin-bottom: 12px;
    }
    .myClassList td .info .title p {
        line-height: 20px;
        margin-top: 5px;
        color: #818181;
    }
    </style>